ARM: s3c64xx: switch to generic watchdog driver reset

Similarly to commit f6361c6b3880 ("ARM: S3C24XX: remove separate restart
code"), the platform watchdog reset code can be removed in favor of
a generic watchdog driver which already handles reset.

This allows removal of a bunch of machine code and fixes also W=1
compile warnings:

    arch/arm/plat-samsung/watchdog-reset.c:29:6: warning: no previous prototype for 'samsung_wdt_reset' [-Wmissing-prototypes]
    arch/arm/plat-samsung/watchdog-reset.c:69:13: warning: no previous prototype for 'samsung_wdt_reset_of_init' [-Wmissing-prototypes]
    arch/arm/plat-samsung/watchdog-reset.c:89:13: warning: no previous prototype for 'samsung_wdt_reset_init' [-Wmissing-prototypes]

The generic watchdog-based system reset is not exactly the same as
before.  The previous method had a fallback to soft_restart() which now
is gone.

The commit also removes a FIXME note about calling s3c64xx_clk_init()
inside s3c64xx_init_irq().  No one fixed this since long time and the
note is not meaningful anymore because watchdog part is removed.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Tomasz Figa <tomasz.figa@gmail.com>

3 files changed, 0 insertions, 100 deletions

diff --git a/arch/arm/plat-samsung/Kconfig b/arch/arm/plat-samsung/Kconfig
index 43a8b2bd16ff..3aca01067b3c 100644
--- a/arch/arm/plat-samsung/Kconfig
+++ b/arch/arm/plat-samsung/Kconfig
@@ -290,12 +290,6 @@ config SAMSUNG_WAKEMASK
 	  and above. This code allows a set of interrupt to wakeup-mask
 	  mappings. See <plat/wakeup-mask.h>
 
-config SAMSUNG_WDT_RESET
-	bool
-	help
-	  Compile support for system restart by triggering watchdog reset.
-	  Used on SoCs that do not provide dedicated reset control.
-
 config DEBUG_S3C_UART
 	depends on PLAT_SAMSUNG
 	int
diff --git a/arch/arm/plat-samsung/Makefile b/arch/arm/plat-samsung/Makefile
index 3db9d2c38258..ce339a96fbf7 100644
--- a/arch/arm/plat-samsung/Makefile
+++ b/arch/arm/plat-samsung/Makefile
@@ -32,4 +32,3 @@ obj-$(CONFIG_SAMSUNG_PM_CHECK)	+= pm-check.o
 obj-$(CONFIG_SAMSUNG_PM_DEBUG)	+= pm-debug.o
 
 obj-$(CONFIG_SAMSUNG_WAKEMASK)	+= wakeup-mask.o
-obj-$(CONFIG_SAMSUNG_WDT_RESET)	+= watchdog-reset.o
diff --git a/arch/arm/plat-samsung/watchdog-reset.c b/arch/arm/plat-samsung/watchdog-reset.c
deleted file mode 100644
index 71d85ff323f7..000000000000
--- a/arch/arm/plat-samsung/watchdog-reset.c
+++ /dev/null
@@ -1,93 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-//
-// Copyright (c) 2008 Simtec Electronics
-//	Ben Dooks <ben@simtec.co.uk>
-//
-// Copyright (c) 2013 Tomasz Figa <tomasz.figa@gmail.com>
-//
-// Watchdog reset support for Samsung SoCs.
-
-#include <linux/clk.h>
-#include <linux/err.h>
-#include <linux/io.h>
-#include <linux/delay.h>
-#include <linux/of.h>
-#include <linux/of_address.h>
-
-#define S3C2410_WTCON			0x00
-#define S3C2410_WTDAT			0x04
-#define S3C2410_WTCNT			0x08
-
-#define S3C2410_WTCON_ENABLE		(1 << 5)
-#define S3C2410_WTCON_DIV16		(0 << 3)
-#define S3C2410_WTCON_RSTEN		(1 << 0)
-#define S3C2410_WTCON_PRESCALE(x)	((x) << 8)
-
-static void __iomem *wdt_base;
-static struct clk *wdt_clock;
-
-void samsung_wdt_reset(void)
-{
-	if (!wdt_base) {
-		pr_err("%s: wdt reset not initialized\n", __func__);
-		/* delay to allow the serial port to show the message */
-		mdelay(50);
-		return;
-	}
-
-	if (!IS_ERR(wdt_clock))
-		clk_prepare_enable(wdt_clock);
-
-	/* disable watchdog, to be safe  */
-	__raw_writel(0, wdt_base + S3C2410_WTCON);
-
-	/* put initial values into count and data */
-	__raw_writel(0x80, wdt_base + S3C2410_WTCNT);
-	__raw_writel(0x80, wdt_base + S3C2410_WTDAT);
-
-	/* set the watchdog to go and reset... */
-	__raw_writel(S3C2410_WTCON_ENABLE | S3C2410_WTCON_DIV16 |
-			S3C2410_WTCON_RSTEN | S3C2410_WTCON_PRESCALE(0x20),
-			wdt_base + S3C2410_WTCON);
-
-	/* wait for reset to assert... */
-	mdelay(500);
-
-	pr_err("Watchdog reset failed to assert reset\n");
-
-	/* delay to allow the serial port to show the message */
-	mdelay(50);
-}
-
-#ifdef CONFIG_OF
-static const struct of_device_id s3c2410_wdt_match[] = {
-	{ .compatible = "samsung,s3c2410-wdt" },
-	{ .compatible = "samsung,s3c6410-wdt" },
-	{},
-};
-
-void __init samsung_wdt_reset_of_init(void)
-{
-	struct device_node *np;
-
-	np = of_find_matching_node(NULL, s3c2410_wdt_match);
-	if (!np) {
-		pr_err("%s: failed to find watchdog node\n", __func__);
-		return;
-	}
-
-	wdt_base = of_iomap(np, 0);
-	if (!wdt_base) {
-		pr_err("%s: failed to map watchdog registers\n", __func__);
-		return;
-	}
-
-	wdt_clock = of_clk_get(np, 0);
-}
-#endif
-
-void __init samsung_wdt_reset_init(void __iomem *base)
-{
-	wdt_base = base;
-	wdt_clock = clk_get(NULL, "watchdog");
-}